package com.dhcc.DRGsHosp.infra.util.license;

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;

public class AESUtil {
	private static final String AES = "AES";
	private static final String CRYPT_KEY = "DHCC_YZXZ_DRGS_F";

	private static byte[] encrypt(byte[] src, String key) throws Exception {
		Cipher cipher = Cipher.getInstance(AES);
		SecretKeySpec securekey = new SecretKeySpec(key.getBytes(), AES);
		cipher.init(1, securekey);
		return cipher.doFinal(src);
	}

	private static byte[] decrypt(byte[] src, String key) throws Exception {
		Cipher cipher = Cipher.getInstance(AES);
		SecretKeySpec securekey = new SecretKeySpec(key.getBytes(), AES);
		cipher.init(2, securekey);
		return cipher.doFinal(src);
	}

	private static String byte2hex(byte[] b) {
		String hs = "";
		String stmp = "";
		for (int n = 0; n < b.length; n++) {
			stmp = Integer.toHexString(b[n] & 0xFF);
			if (stmp.length() == 1)
				hs = hs + "0" + stmp;
			else
				hs = hs + stmp;
		}
		return hs.toUpperCase();
	}

	private static byte[] hex2byte(byte[] b) {
		if (b.length % 2 != 0)
			throw new IllegalArgumentException("长度不是偶数");
		byte[] b2 = new byte[b.length / 2];
		for (int n = 0; n < b.length; n += 2) {
			String item = new String(b, n, 2);
			b2[(n / 2)] = (byte) Integer.parseInt(item, 16);
		}
		return b2;
	}

	public static final String decrypt(String data) {
		try {
			return new String(decrypt(hex2byte(data.getBytes()), CRYPT_KEY));
		} catch (Exception localException) {
		}
		return null;
	}

	public static final String encrypt(String data) {
		try {
			return byte2hex(encrypt(data.getBytes(), CRYPT_KEY));
		} catch (Exception localException) {
		}
		return null;
	}
}